At the early age people used pebbles, stones, sticks, scratches, symbols and finger tips to count, which were later replaced by numbers.

The history of computing is divided into three ages during which man invented and improved different types of calculating machines. These ages are,

* Dark Age - 300 BC to 1890

* Middle age - 1890 AD to 1944

* Modern age - since 1944 AD

Dark Age (3000 BC to 1890 AD

ABACUS

About 3000 years BC, Chinese developed the first calculating machine named Abacus or Soroban.

Abacus consists of a rectangular wooden frame having rods which carry round beads. Counting is done by shifting the beads from one side to another.

OUGHTRED’S SLIDE RULES

In 1632 AD William Oughtred; an English mathematician developed a slide rule. This device consists of two movable rules placed side by side on which number were marked.

PASCAL’S CALCULATOR

Blasé Pascal (1623-1662), French developed the first mechanical calculating machine in 1642. This machine consists of gears, wheels and dials. It was capable of adding and subtracting operations.

GOTTEFRIED WILHOLM LEIBNITZ

In 1671, a German, Gottfried Von Leibnitz (1646-1716) improved Pascal’s calculator to make it capable of performing all math operations.

JACQUARD’S LOOM

In 1801, a French, Joseph Marie Jacquard developed the first punch card machine.

BABBAGE DIFFERENCE ENGINE

Charles Babbage (1792-1871) an English mathematician also called Father of modern computer. As he gave the true concept of computer at Cambridge University, he developed Babbage Difference Engine in 1823 and Babbage Analytical Engine in 1833.

Lady Ada Augusta an assistant of Babbage is called the first programmer.

Middle Age (1890 AD TO 1944 AD)

DOCTOR HERMAN HOLLERITH

In 1880s Herman Hollerith an American developed a machine which used punch card system. The machine could sense and punch holes, recognize the number and make required calculations. This machine was first used in 1890s by American Census Bureau.

HOWARD AIKEN- MARK-1 COMPUTER

In 1937, Professor Howard Aiken builds the first electro-mechanical computer Mark-1, by trying to combine Babbage’s theory and Hollerith’s punching technologies. He completed his project in 1944 with the help of IBM Engineers.

Mark 1 could multiply two, twenty digit numbers in 5 seconds and made a lot of noise. It had a shape like a monster about 50 feet long, 8 feet high, having wiring of length equal to distance 800km and had thousand ends of electro-magnetic relays.

ABC (ATANASOFF BERRY COMPUTER)

ABC a special purpose computer was developed in 1938 by Dr. John Vincent Atanasoff and Clifford Berry at Iowa State College, USA.

Modern Ages (Since 1944 AD)

JOHN VON NEUMAN

in 1945; Dr. John Von Neumann suggested the concept of Automatic Data Processing (ADP) according to the stored program and data. ENIAC

(FIRST ELECTRONIC COMPUTER)

Electronic Numerical Integrator And Calculator (ENIAC) was the first electronic computer made in 1946 by John Presper Eckert and John Williams Mauchly, at the University of Pennsylvania, USA. This was based on decimal number system and it has no memory.

It could perform 5000 additions or 350 multiplications in one second. It contained 18000 vacuum tubes, 70,000 resistors, 10,000 capacitors and 60,000 switches and occupied a two room car garage. It consumed 150 kW of power. It weighed 27 tons.

EDSAC (FIRST STORED PROGRAM COMPUTER)

Electronic Delay Storage Automatic Computer (EDSAC) was first computer based on stored program concept. It was completed by Mourice Wilkes at Cambridge University in 1949.

EDVAC

Electronic Discrete Variable Automatic Computer (EDVAC) was built by John Williams Mauchly, John Presper Eckert at Moore School, Pennsylvania in 1951.

UNIVAC (FIRST COMMERCIAL COMPUTER)

UNIVersal Automatic Computer (UNIVAC) was the first commercially used computer made by...